Phase transitions in high-Tc superconductors and the anisotropic three-dimensional XY model
نویسندگان
چکیده
We carry out simulations of the anisotropic uniformly frustrated three-dimensional XY model, as a model for vortex line fluctuations in high-Tc superconductors. We compute the phase diagram as a function of temperature and anisotropy, for a fixed applied magnetic field B . We find that superconducting coherence parallel to B persists into the vortex line liquid state, vanishing at a Tcz above the melting Tm . Both Tcz and Tm are found in general to lie well below the crossover Tc2 from the vortex line liquid to the normal state. @S0163-1829~97!12117-8#
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